Stable water jet hull



May 15, 1956 J. v. MANIS 2,745,3370

STABLE WATER JET HULL Filed July 13, 1953 5 Sheets-Sheet 1 IN V EN TOR.0

3M W W y 15, 1956 J. v. MANIS 2,745,370

STABLE WATER JET HULL Filed July 15, 1953 3 SheetsSheet 2 INVENTOR.

y 1956 J. v. MANIS STABLE WATER JET HULL 3 Sheets-Sheet 3 Filed July 13,1953 ]N V EN TOR.

United States Patent STABLE WATER JET HULL James Vincent Manis, Oreland,Pa.

Application July 13, 1953, Serial No. 367,388

1 Claim. (Cl. 115-16) The invention relates to a highly stable boat hullstructure having novel means to increase stability compared to a boat orship having many times its displacement and providing a structure ofmaximum efliciency of engine operation.

To accomplish this at present a ship must be of considerabledisplacement in order to get the stability necessary, thus sacrificingspeed, maneuverability, and maximum efliciency of engine operation.Expensive items such as gyro-stabilizers, often abbreviated to gyro, aresometimes installed which help stabilize the craft but add weight andare costly.

Gyros are practical only on large vessels.

An object of this invention is to decrease the weight of the craft bythe use of an air cushioning effect by the means of an overhangstructure on the port and starboard sides of the craft, runninglongitudinally along the complete length of the craft.

Another object of the invention is to construct a tube or tubes, that isa tunnel or tunnels, longitudinally through the craft below the waterline, thus using the water flowing through it or them as ballast as thecraft rolls, yaws, or pitches. The tube or tubes also serve as screwhousings to increase their efiiciency, by controling or restricting theback wash directly to the rear in a concentrated jet action thus givingmaximum engine efiiciency.

Still another aim is to provide instant control response, made possibleby mounting the rudder or rudders directly on the center lines of thistube or tubes.

Another purpose of this invention is to decrease the weight of a craftwithout sacrifice of pay load.

Still another object is to increase the stability of the craft insofaras pitch, yaw, and roll is concerned.

An additional object is to increase maneuverability f the craft byincreasing rudder sensitivity. 7

Another object of this invention is to increase the efficiency of thescrew and engine operation by creating a controlled or concentratedwater jet flow to increase propulsion.

Other objects and many of the attendant advantages of this inventionwill be readily appreciated as the same becomes beter understood byreference to the following detailed description when considered inconnection with the accompanying drawings in which like referencenumerals designate like parts throughout the figures thereof andwherein:

Fig. 1 shows a cross sectional view of a speed boat,

Fig. 2 illustrates a side elevation with cut-aways to show the tubestructure and screw location,

Fig. 3 shows a plan view illustrating an airfoil cross section.

Fig. 3a is a sectional view of a portion of the hull taken along line3a3a, Fig. 3.

Fig. 4 presents a cross-sectional View of a speed boat showing analternate form of the inventive device.

Fig. 5 shows a cross-sectional view of ring gear and gear train meansassociated with the screw propeller of Fig. 2.

Referring to the drawings, wherein like reference characters designatelike or corresponding parts throughout the several views:

A V-type hull 5 curves upwardly and outwardly as it reaches close to thetop of the deck 6 and as it curves outwardly to a desired distance itstarts to curve downwardly as shown at 7 to dip below the water line 8.This forms tunnels 9 and 10 approximately semi-circular in crosssectionwhich run longitudinally along the'port and starboard outer sides of thecraft. thickness cross-section 11 is of an airfoil section to give thecraft added lift and cushioning effect as the trapped air rushes throughthe tunnels at a fair speed.

A tube 12 runs longitudinally through the craft below the water line,entrance aperture 13 being disposed at the prow and the exit aperture 14at the stern. The water rushing through this tube tends to stabilize theship insofar as roll, yaw, and pitch are concerned (since the weight ofthe volume of water displaced by the tube acts as ballast when the shiptends to pitch, roll, or yaw). If desired, a plurality of tubes may beinserted below the water line and longitudinally of the boat, as forexample where a plurality of screws are to be used for propulsionpurposes or where more ballast effect is necessary. The tubes may bemade separate from or integral with the hull as desired.

The screw 15 is also housed in this tube. (A suggested method oftransmitting power to the screw if not by a shaft would be to cast thescrew inside of a ring 16 having an approximate diameter equal to theinside diameter of the tube. The outer rim of the ring would have gearteeth that would mesh with another arrangement of gears transmittingenergy from the power unit.) Having the screw thus located would preventany side energy waste, since the back wash from the screw would berestricted or controlled by the walls of the tube. This method wouldgive a concentrated column of energy with force directed at the exit 14of the tube. As shown in Fig. 2 a plurality of screws 15 in tandem mightbe housed in the tube. A preferred location of the screw or screws 15 toreduce friction loss and improve power transmission would be relativelynear the stern as compared with distance from the bow as indicated inFig. 2.

In addition, the location of the rudder 17 which may be mounted directlyto the rear of and on a center line with the tube is subject to theconcentrated jet water or energy blast coming out of it. This givesinstant response reaction.

In Fig. 4 a cross section shows a hollow V keel tunnel construction 18in place of the tubular construction 12. This may be used when foundmore practical on some types of V hulls. The screw is located inside thehollow V keel 18 as in the tubular type.

As shown in Fig. 5, the outer rim of ring 16 has gear teeth 24 which maymesh with the teeth of gear 21, through an opening 22 which may beprovided at the top of the tube 12. If desired ring bearings (not shown)may be disposed on the screw housing 16 and rotated in grooved guides(not shown) along tube 12 and spaced longitudinally from the outer rimgear of ring 16 so as to avoid power loss due to undue friction orpossible Wobbling of ring 16. Gear 21 would be mounted in bearings 34 ina waterproof gear box 23. Shaft 35 on which gear 21 is mounted may bedriven by a gear train generally designated at 25 and which may transmitpower from engine drive shaft 26. The arrangement of the gear traincould be designed to increase or decrease the R. P. M. (revolutions perminute) as desired.

It is within the scope of this invention to dispose tubes externally ofspecially built or existing hulls varying location as found feasible asfor example underneath the hull structure.

The longitudinal Wall I Obviously many modifications and variations ofthe present invention are possible in the light of the above teachings.It is therefore to be understood that within the scope of the appendedclaim the invention may be practiced otherwise than as specificallydescribed.

I claim:

A marine craft comprising a V-shaped hull having an upper-deck portionand a below-Water portion, said hull having diverging sides curvingupwardly and outwardly at the upper deck portion and thence curvingdown- Wardly', the router downward tip of the sides being in normallysubmerged position to form a tunnel approximately semi-circular incross-section running the com.- plete length on each side of the craft,said sides at the tunnel surrounding areas being of airfoil section sothat during rapid motion added lift and cushioning will be effected onthe craft as trapped air rushes through the tunnels, a tube disposedlongitudinally through the craft below the waterline, said tube havingan entrance aperture at the wow of the craft and an exit aperture at thestern, topermit Water to rush through the tube in motion of the craft,thereby stabilizing the craft with respect to roll, yaw, and pitch,since the weight of the Water dis- 7 placed by the tube acts as ballastwhen the craft tends to outer rim comprising gear teeth, gear trainmeans meshing with thegear teeth of saidring to thereby transmit powerto said screw, thereby preventing side energy waste since the back Washfrom the screw is restricted by the tube walls to present a concentratedcolumn of energy force directed at the tube exit during operation ofsaid craft, a rudder disposed directly to therear of and on a centerline with'the tube, saidrudder thereby being subject to the concentratedjet of water from the tube in craft operating condition to give rapidrudder response action, the craft thereby possessing 'for its sizecharacteristics of high stability, high efiiciency of engine operation,rapid control response and relatively large pay load capability.

References Cited in the file of this patent UNITED STATES PATENTS FranceMar. 6, 1939

